The passageways and waiting areas of Grand Central's subway stations are like a bustling city, an underground community - but without a skyline. This mosaic artwork brings architectural views down below.

Ferrara has long been interested in the simple and repetitive forms of building, and she uses forms that are simple and schematic, almost primitive-looking structures. Taken together, they lend a unity and meditative character to the space; as people move through the platforms and passageways, the images seem to shift, and no two vistas are the same. Ferrara thinks of these as pieces of a mathematical puzzle. The spare simplicity and economy of design attracts viewers. Nothing is casual or unintentional in the artist's design, which she describes: "This sequence of stripe/image is calculated. It can be seen as images on a strip of film, or a line of faces framed in the windows of a passing train."